Atypical Migration in Serum Immunofixation of Immunoglobulin A with Masked kappa Light Chains: a Case Report and Review of the Literature.

BACKGROUND: We report a case of a patient with immunoglobulin A multiple myeloma associated with a masked kappa light chain. Serum immunofixation showed a monoclonal band in the IgA heavy chain lane without corre-spondence with the light chain and a monoclonal band in total kappa light chain lane without correspondence with the heavy chain. METHODS: To distinguish between heavy chain disease and immunoglobulin with "masked" light chains, two tubes containing the patient's serum were incubated with a very high concentration of anti-total kappa and anti-total lambda antisera for 48 hours at 4°C in order to facilitate immunoprecipitation of the involved light chain. After centrifugation, the supernatant was analyzed by using the IFs method on the Hydrasys 2 Scan Focusing Sebia® without dilution. Then we applied the anti-IgA, anti-total kappa and anti-total lambda antisera. RESULTS: The serum immunofixation test of the sample treated with a high concentration of anti-total kappa showed the disappearance of the monoclonal bands corresponding to IgA heavy chain lane and kappa light chain lane, indicating that precipitation had occurred and that the IgA did have kappa light chains that could not be detected by the standard immunofixation protocol. The serum immunofixation test of the sample treated with anti-total lambda showed the disappearance of the polyclonal background in lambda light chain lane, confirming that the precipitation with lambda light chains according to the previously mentioned protocol has done well. CONCLUSIONS: This case illustrates some of the difficulties encountered and the corrective actions that can be taken for the detection of immunoglobulins with masked light chains.

Monoclonal Immunoglobulin Associated with Monoclonal Free Light Chains Invisible on Capillary Electrophoresis.

BACKGROUND: We report the case of a monoclonal immunoglobulin of IgM Lambda isotype associated with monoclonal lambda-type free light chains not detected by capillary electrophoresis but identified by immunofixation. METHODS: Capillary electrophoresis showed hypoproteinemia and an inflammatory syndrome. The IF realized on Hydrasys 2 Scan Focusing Sebia® reveals an IgM monoclonal band and two monoclonal bands in the total lambda. A second IF is performed using anti IgM, anti IgD, anti IgE and anti-total and -free lambda light chains as antisera. It reveals the presence of a monoclonal protein isotype IgM Lambda with free light chains. In view of these discordant results, an immunosubtraction was performed on the same sample showing no abnormality. RESULTS: Our patient has a monoclonal IgM Lambda with lambda monoclonal free light chains all masked on capillary electrophoresis and therefore not detected. CONCLUSIONS: Capillary electrophoresis techniques are incrementally becoming the techniques of choice in medical laboratories as a replacement for gel electrophoresis, due to their automation and better sensitivity. However, in some cases, a monoclonal immunoglobulin may not be detected by capillary technique and may cause an inaccurate interpretation.

Successful management of synchronous recurrent breast carcinoma with chronic myelogenous leukemia: a case report.

BACKGROUND: Survival is increasing after early breast cancer revealing frequent relapses and possibility of developing secondary malignancies. The concomitant occurrence of these two events is exceptionally disastrous and lethal. We report a case of a Moroccan woman who was successfully managed for synchronous recurrent breast carcinoma and chronic myelogenous leukemia. CASE PRESENTATION: A 42-year-old Moroccan woman was diagnosed with localized breast carcinoma in 2008. She received six cycles of an adjuvant chemotherapy regimen, radiation therapy and hormonal therapy by tamoxifen. After completion of 5 years of tamoxifen our patient reported asthenia; a physical examination found hepatomegaly, massive splenomegaly measuring 21 cm and supraclavicular lymphadenopathy. The staging showed lung and liver metastases. Morphology and immunohistochemical profile of this metastasis identified an adenocarcinoma of mammary origin. In parallel, the diagnosis of chronic myeloid leukemia was suspected because of the presence of a leukocytosis at 355 × 109/L, with circulating blasts of 4%. Chronic myeloid leukemia was confirmed by a bone marrow biopsy with the presence of Ph chromosome on cytogenetical analysis. Daily imatinib was ordered concurrently with chemotherapy-type docetaxel. The metastases were stable after nine courses of chemotherapy. Due to breast cancer progression 4 months later, bevacizumab and capecitabine were introduced. A major molecular response was achieved after 12 and 18 months. She has now completed 2 years of follow-up, still on a major molecular response, and is undergoing imatinib and capecitabine treatment. CONCLUSIONS: Leukocytosis in breast cancer patients can reveal chronic myeloid leukemia. It may warrant a workup to find the underlying etiology, which could include a secondary hematological malignancy.